drivers/usb/gadget/function/uvc_v4l2.c

   1 // SPDX-License-Identifier: GPL-2.0+
   2 /*
   3  *      uvc_v4l2.c  --  USB Video Class Gadget driver
   4  *
   5  *      Copyright (C) 2009-2010
   6  *          Laurent Pinchart (laurent.pinchart@ideasonboard.com)
   7  */
   8
   9 #include <linux/kernel.h>
  10 #include <linux/device.h>
  11 #include <linux/errno.h>
  12 #include <linux/list.h>
  13 #include <linux/videodev2.h>
  14 #include <linux/vmalloc.h>
  15 #include <linux/wait.h>
  16
  17 #include <media/v4l2-dev.h>
  18 #include <media/v4l2-event.h>
  19 #include <media/v4l2-ioctl.h>
  20
  21 #include "f_uvc.h"
  22 #include "uvc.h"
  23 #include "uvc_queue.h"
  24 #include "uvc_video.h"
  25 #include "uvc_v4l2.h"
  26
  27 /* --------------------------------------------------------------------------
  28  * Requests handling
  29  */
  30
  31 static int
  32 uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
  33 {
  34         struct usb_composite_dev *cdev = uvc->func.config->cdev;
  35         struct usb_request *req = uvc->control_req;
  36
  37         if (data->length < 0)
  38                 return usb_ep_set_halt(cdev->gadget->ep0);
  39
  40         req->length = min_t(unsigned int, uvc->event_length, data->length);
  41         req->zero = data->length < uvc->event_length;
  42
  43         memcpy(req->buf, data->data, req->length);
  44
  45         return usb_ep_queue(cdev->gadget->ep0, req, GFP_KERNEL);
  46 }
  47
  48 /* --------------------------------------------------------------------------
  49  * V4L2 ioctls
  50  */
  51
  52 struct uvc_format {
  53         u8 bpp;
  54         u32 fcc;
  55 };
  56
  57 static struct uvc_format uvc_formats[] = {
  58         { 16, V4L2_PIX_FMT_YUYV  },
  59         { 0,  V4L2_PIX_FMT_MJPEG },
  60 };
  61
  62 static int
  63 uvc_v4l2_querycap(struct file *file, void *fh, struct v4l2_capability *cap)
  64 {
  65         struct video_device *vdev = video_devdata(file);
  66         struct uvc_device *uvc = video_get_drvdata(vdev);
  67         struct usb_composite_dev *cdev = uvc->func.config->cdev;
  68
  69         strlcpy(cap->driver, "g_uvc", sizeof(cap->driver));
  70         strlcpy(cap->card, cdev->gadget->name, sizeof(cap->card));
  71         strlcpy(cap->bus_info, dev_name(&cdev->gadget->dev),
  72                 sizeof(cap->bus_info));
  73
  74         cap->device_caps = V4L2_CAP_VIDEO_OUTPUT | V4L2_CAP_STREAMING;
  75         cap->capabilities = cap->device_caps | V4L2_CAP_DEVICE_CAPS;
  76
  77         return 0;
  78 }
  79
  80 static int
  81 uvc_v4l2_get_format(struct file *file, void *fh, struct v4l2_format *fmt)
  82 {
  83         struct video_device *vdev = video_devdata(file);
  84         struct uvc_device *uvc = video_get_drvdata(vdev);
  85         struct uvc_video *video = &uvc->video;
  86
  87         fmt->fmt.pix.pixelformat = video->fcc;
  88         fmt->fmt.pix.width = video->width;
  89         fmt->fmt.pix.height = video->height;
  90         fmt->fmt.pix.field = V4L2_FIELD_NONE;
  91         fmt->fmt.pix.bytesperline = video->bpp * video->width / 8;
  92         fmt->fmt.pix.sizeimage = video->imagesize;
  93         fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
  94         fmt->fmt.pix.priv = 0;
  95
  96         return 0;
  97 }
  98
  99 static int
 100 uvc_v4l2_set_format(struct file *file, void *fh, struct v4l2_format *fmt)
 101 {
 102         struct video_device *vdev = video_devdata(file);
 103         struct uvc_device *uvc = video_get_drvdata(vdev);
 104         struct uvc_video *video = &uvc->video;
 105         struct uvc_format *format;
 106         unsigned int imagesize;
 107         unsigned int bpl;
 108         unsigned int i;
 109
 110         for (i = 0; i < ARRAY_SIZE(uvc_formats); ++i) {
 111                 format = &uvc_formats[i];
 112                 if (format->fcc == fmt->fmt.pix.pixelformat)
 113                         break;
 114         }
 115
 116         if (i == ARRAY_SIZE(uvc_formats)) {
 117                 printk(KERN_INFO "Unsupported format 0x%08x.\n",
 118                         fmt->fmt.pix.pixelformat);
 119                 return -EINVAL;
 120         }
 121
 122         bpl = format->bpp * fmt->fmt.pix.width / 8;
 123         imagesize = bpl ? bpl * fmt->fmt.pix.height : fmt->fmt.pix.sizeimage;
 124
 125         video->fcc = format->fcc;
 126         video->bpp = format->bpp;
 127         video->width = fmt->fmt.pix.width;
 128         video->height = fmt->fmt.pix.height;
 129         video->imagesize = imagesize;
 130
 131         fmt->fmt.pix.field = V4L2_FIELD_NONE;
 132         fmt->fmt.pix.bytesperline = bpl;
 133         fmt->fmt.pix.sizeimage = imagesize;
 134         fmt->fmt.pix.colorspace = V4L2_COLORSPACE_SRGB;
 135         fmt->fmt.pix.priv = 0;
 136
 137         return 0;
 138 }
 139
 140 static int
 141 uvc_v4l2_reqbufs(struct file *file, void *fh, struct v4l2_requestbuffers *b)
 142 {
 143         struct video_device *vdev = video_devdata(file);
 144         struct uvc_device *uvc = video_get_drvdata(vdev);
 145         struct uvc_video *video = &uvc->video;
 146
 147         if (b->type != video->queue.queue.type)
 148                 return -EINVAL;
 149
 150         return uvcg_alloc_buffers(&video->queue, b);
 151 }
 152
 153 static int
 154 uvc_v4l2_querybuf(struct file *file, void *fh, struct v4l2_buffer *b)
 155 {
 156         struct video_device *vdev = video_devdata(file);
 157         struct uvc_device *uvc = video_get_drvdata(vdev);
 158         struct uvc_video *video = &uvc->video;
 159
 160         return uvcg_query_buffer(&video->queue, b);
 161 }
 162
 163 static int
 164 uvc_v4l2_qbuf(struct file *file, void *fh, struct v4l2_buffer *b)
 165 {
 166         struct video_device *vdev = video_devdata(file);
 167         struct uvc_device *uvc = video_get_drvdata(vdev);
 168         struct uvc_video *video = &uvc->video;
 169         int ret;
 170
 171         ret = uvcg_queue_buffer(&video->queue, b);
 172         if (ret < 0)
 173                 return ret;
 174
 175         return uvcg_video_pump(video);
 176 }
 177
 178 static int
 179 uvc_v4l2_dqbuf(struct file *file, void *fh, struct v4l2_buffer *b)
 180 {
 181         struct video_device *vdev = video_devdata(file);
 182         struct uvc_device *uvc = video_get_drvdata(vdev);
 183         struct uvc_video *video = &uvc->video;
 184
 185         return uvcg_dequeue_buffer(&video->queue, b, file->f_flags & O_NONBLOCK);
 186 }
 187
 188 static int
 189 uvc_v4l2_streamon(struct file *file, void *fh, enum v4l2_buf_type type)
 190 {
 191         struct video_device *vdev = video_devdata(file);
 192         struct uvc_device *uvc = video_get_drvdata(vdev);
 193         struct uvc_video *video = &uvc->video;
 194         int ret;
 195
 196         if (type != video->queue.queue.type)
 197                 return -EINVAL;
 198
 199         /* Enable UVC video. */
 200         ret = uvcg_video_enable(video, 1);
 201         if (ret < 0)
 202                 return ret;
 203
 204         /*
 205          * Complete the alternate setting selection setup phase now that
 206          * userspace is ready to provide video frames.
 207          */
 208         uvc_function_setup_continue(uvc);
 209         uvc->state = UVC_STATE_STREAMING;
 210
 211         return 0;
 212 }
 213
 214 static int
 215 uvc_v4l2_streamoff(struct file *file, void *fh, enum v4l2_buf_type type)
 216 {
 217         struct video_device *vdev = video_devdata(file);
 218         struct uvc_device *uvc = video_get_drvdata(vdev);
 219         struct uvc_video *video = &uvc->video;
 220
 221         if (type != video->queue.queue.type)
 222                 return -EINVAL;
 223
 224         return uvcg_video_enable(video, 0);
 225 }
 226
 227 static int
 228 uvc_v4l2_subscribe_event(struct v4l2_fh *fh,
 229                          const struct v4l2_event_subscription *sub)
 230 {
 231         if (sub->type < UVC_EVENT_FIRST || sub->type > UVC_EVENT_LAST)
 232                 return -EINVAL;
 233
 234         return v4l2_event_subscribe(fh, sub, 2, NULL);
 235 }
 236
 237 static int
 238 uvc_v4l2_unsubscribe_event(struct v4l2_fh *fh,
 239                            const struct v4l2_event_subscription *sub)
 240 {
 241         return v4l2_event_unsubscribe(fh, sub);
 242 }
 243
 244 static long
 245 uvc_v4l2_ioctl_default(struct file *file, void *fh, bool valid_prio,
 246                        unsigned int cmd, void *arg)
 247 {
 248         struct video_device *vdev = video_devdata(file);
 249         struct uvc_device *uvc = video_get_drvdata(vdev);
 250
 251         switch (cmd) {
 252         case UVCIOC_SEND_RESPONSE:
 253                 return uvc_send_response(uvc, arg);
 254
 255         default:
 256                 return -ENOIOCTLCMD;
 257         }
 258 }
 259
 260 const struct v4l2_ioctl_ops uvc_v4l2_ioctl_ops = {
 261         .vidioc_querycap = uvc_v4l2_querycap,
 262         .vidioc_g_fmt_vid_out = uvc_v4l2_get_format,
 263         .vidioc_s_fmt_vid_out = uvc_v4l2_set_format,
 264         .vidioc_reqbufs = uvc_v4l2_reqbufs,
 265         .vidioc_querybuf = uvc_v4l2_querybuf,
 266         .vidioc_qbuf = uvc_v4l2_qbuf,
 267         .vidioc_dqbuf = uvc_v4l2_dqbuf,
 268         .vidioc_streamon = uvc_v4l2_streamon,
 269         .vidioc_streamoff = uvc_v4l2_streamoff,
 270         .vidioc_subscribe_event = uvc_v4l2_subscribe_event,
 271         .vidioc_unsubscribe_event = uvc_v4l2_unsubscribe_event,
 272         .vidioc_default = uvc_v4l2_ioctl_default,
 273 };
 274
 275 /* --------------------------------------------------------------------------
 276  * V4L2
 277  */
 278
 279 static int
 280 uvc_v4l2_open(struct file *file)
 281 {
 282         struct video_device *vdev = video_devdata(file);
 283         struct uvc_device *uvc = video_get_drvdata(vdev);
 284         struct uvc_file_handle *handle;
 285
 286         handle = kzalloc(sizeof(*handle), GFP_KERNEL);
 287         if (handle == NULL)
 288                 return -ENOMEM;
 289
 290         v4l2_fh_init(&handle->vfh, vdev);
 291         v4l2_fh_add(&handle->vfh);
 292
 293         handle->device = &uvc->video;
 294         file->private_data = &handle->vfh;
 295
 296         uvc_function_connect(uvc);
 297         return 0;
 298 }
 299
 300 static int
 301 uvc_v4l2_release(struct file *file)
 302 {
 303         struct video_device *vdev = video_devdata(file);
 304         struct uvc_device *uvc = video_get_drvdata(vdev);
 305         struct uvc_file_handle *handle = to_uvc_file_handle(file->private_data);
 306         struct uvc_video *video = handle->device;
 307
 308         uvc_function_disconnect(uvc);
 309
 310         mutex_lock(&video->mutex);
 311         uvcg_video_enable(video, 0);
 312         uvcg_free_buffers(&video->queue);
 313         mutex_unlock(&video->mutex);
 314
 315         file->private_data = NULL;
 316         v4l2_fh_del(&handle->vfh);
 317         v4l2_fh_exit(&handle->vfh);
 318         kfree(handle);
 319
 320         return 0;
 321 }
 322
 323 static int
 324 uvc_v4l2_mmap(struct file *file, struct vm_area_struct *vma)
 325 {
 326         struct video_device *vdev = video_devdata(file);
 327         struct uvc_device *uvc = video_get_drvdata(vdev);
 328
 329         return uvcg_queue_mmap(&uvc->video.queue, vma);
 330 }
 331
 332 static __poll_t
 333 uvc_v4l2_poll(struct file *file, poll_table *wait)
 334 {
 335         struct video_device *vdev = video_devdata(file);
 336         struct uvc_device *uvc = video_get_drvdata(vdev);
 337
 338         return uvcg_queue_poll(&uvc->video.queue, file, wait);
 339 }
 340
 341 #ifndef CONFIG_MMU
 342 static unsigned long uvcg_v4l2_get_unmapped_area(struct file *file,
 343                 unsigned long addr, unsigned long len, unsigned long pgoff,
 344                 unsigned long flags)
 345 {
 346         struct video_device *vdev = video_devdata(file);
 347         struct uvc_device *uvc = video_get_drvdata(vdev);
 348
 349         return uvcg_queue_get_unmapped_area(&uvc->video.queue, pgoff);
 350 }
 351 #endif
 352
 353 const struct v4l2_file_operations uvc_v4l2_fops = {
 354         .owner          = THIS_MODULE,
 355         .open           = uvc_v4l2_open,
 356         .release        = uvc_v4l2_release,
 357         .unlocked_ioctl = video_ioctl2,
 358         .mmap           = uvc_v4l2_mmap,
 359         .poll           = uvc_v4l2_poll,
 360 #ifndef CONFIG_MMU
 361         .get_unmapped_area = uvcg_v4l2_get_unmapped_area,
 362 #endif
 363 };
 364